Method and apparatus for needling a fibrous web to form a textile product



4 Sheets-Sheet 1 S K L a a a M HWU o 7% 2 TD /R m m A w WM T m% w w I. mVA March 20, 1962 R. D. WELLS METHOD AND APPARATUS FOR NEEDLING AFIBROUS WEB TO FORM A TEXTILE PRODUCT Filed June 13, 1958 m m a w 2 2 Iu h 4/ s G I F .5 M n A n m- ..Lb a, M m 02.70 M a 6 Q P m coo NN 5 F000 F. w am 000 l 4 (s. G w F R. D. WELLS March 20, 1962 3,025,586METHOD AND APPARATUS FOR NEEDLING A FIBROUS WEB TO FORM A TEXTILEPRODUCT 4 Sheets-Sheet 2 Filed June 13, 1958 FIG. 25

I l 2 s gllir' FIG. 23 841 FIG. 2 s I FIG 27 m E mw mu E VD M 6 7 1 m m9R m I O I 0 8 6 6 m 2 B m 3 mm m m ATTORNEY March 20, 1962 R. D. WELLS3,025,586

METHOD AND APPARATUS FOR NEEDLING A FIBROUS WEB TO FORM A TEXTILEPRODUCT Filed June 13, 1958 4 Sheets-Sheet L5 ll 9 l FIG. IO

FIG. 9 54 INVENTOR RICHARD D. WELL 6AM 7AM ATTORNEY March 20, 1962 R. D.WELLS 3,025,586

METHOD AND APPARATUS FOR NEEDLING A FIBROUS WEB TO FORM A TEXTILEPRODUCT 4 Sheets-Sheet 4 Filed June 13, 1958 FIG. 32

INVENTOR RlCHARD D. WELLS United States Patent @f 3,tl25,56 METHOD ANDAPPARATUS FOR NEEDLINIG A FIBROUS WEB T9 FORM A TEXTILE PRODUCT RichardD. Wells, Auburn, Maine, assignor to tjrornpton dz Knowles Corporation,Worcester, Mass, at corporation of Massachusetts Filed June 13, .1953,Ser. No. 741,859 24 Claims. (Cl. 28--4) This invention relates tomethods and apparatus for treating or acting on a group of fibersloosely assembled in a web and also to the product made by the methodand apparatus.

Current methods for manufacturing so-called nonwoven fabrics ordinarilyemploy some form of adhesive to hold the fibers together, or depend uponthe use of thermoplastic fibers which can be stuck to each other by theheating process. Such fabrics, however, do not have the same feel ortexture commonly found in knit and woven fabrics. In order to attain amore acceptable feel it is an important object of the invention toeliminate the use of objectionable amounts of adhesive or thermoplasticfibers by providing methods and apparatus to effect mechanicalinterlocking or bonding of fibers.

The batt or web of fibers ordinarily does not have suflicient strengthto withstand the strains of ordinary usage and it is a further object ofthe invention to provide methods and apparatus for gathering certain ofthe fibers into reenforcing yarn-like structures which act to strengthenand reenforce the web.

By way of illustrating the invention five types of structure are setforth in one of which the reenforcing zones or structures are transverseof the plane of the web and extend from at least one surface of the webinto the latter in such manner as to gather or twist fibers inconcentrations which are connected to each other by fibers which partakeonly partly of the twisted concentrations. In the second form of theinvention reenforcing yarnlike structures are formed lengthwise in asingle batt or web of fibers, and in the third form two batts or websare brought into tangential or at least surface contact with each otherand the reenforcing structures are made from fibers drawn from bothwebs. In the fourth form reenforcing structures are formed on both sidesof a web. In the fifth form the fibers are gathered together to form ayarn-like structure which is not necessarily connected to any similarstructure but can be used either as a step for further treatment toproduce yarns or can be used directly as produced as will be set forthherein after.

In order to produce the reenforcing yarn-like structures it is animportant object of the invention to subject the fibers in localizedzones of the Web to rotary action which will coil at least some of thefibers on them selves and wherein some of the coiled fibers extend intoadjacent areas of the web to have frictional contact with other fibersnot necessarily entangled in the yarn structure.

It is a further object of the invention to use fibers some of which willhave a length sufficient to extend from one reenforcing structure to anadjacent similar structure and become coiled into both structures sothat the lateral strength of the web is increased.

It is a still further object of the invention to subject localized areasof the web to the action of rotating needles which when rotated areeffective due to characteristics such as barbs to collect some of thefibers into the aforesaid yarn-like structures. As the needles arerotated on their axes the web is fed forwardly in a direction away fromthe needles in order to produce continuous yarn-like structures.

ice

Many nonwoven fabrics lack the property of drape and are also onlyslightly elastic in any direction, particularly lengthwise andcrosswise. It is an important object of the present invention to providea process and apparatus to produce a product in the nature of a nonwovenfabric which is capable of elastic stretch lengthwise and alsocrosswise.

This latter characteristic of the fabric is attained by coiling some ofthe fibers helically so that the yarn-like structure has lengthwiseelasticity and spirally coiling other fibers, or parts of those coiledhelically, to permit uncoiling to provide transverse elasticity.

In the accompanying drawings examples are given of each of the fivetypes of structures already mentioned and apparatus for producing thestructures and methods employed to produce them are described.

FIG. 1 is a combined plan and side view of a fabric made according tothe first form of the invention wherein short reenforcing structures areassembled out of fibers in the web and extend at least partway throughthe web from one side to the other,

FIG. 2 is a view similar to FIG. 1 but wherein lengthwise yarn-likestructures have been formed in a single web of fibers,

FIG. 3 is a view similar to FIG. 2 but wherein the web has been made byjoining two distinct webs by reenforcing yarn-like structures locatedbetween the two webs and having their fibers drawn from each of the Websso that the latter are closely bonded to each other,

FIG. 4 is a view showing an end of a fabric similar to that shown inFIG. 2 but with a row of reenforcing yarn-like structure on both sidesthereof,

FIG. 5 is a view similar to FIG. 1 but. showing a single yarn-likestructure formed as such without reference to a fabric,

FIG. 6 is a side elevation in diagrammatic form showing a machine forproducing the type of fabric shown in FIG. 1,

FIG. 7 is a diagrammatic elevation of a machine looking in the directionof feed of the web to be acted on for producing for instance the typesof fabrics shown in FIGS. 3 or 4,

FIG. 8 is a diagrammatic side view looking in the direction of arrow 8,FIG. 7,

FIG. 9 is an enlarged section on line 9-9, FIG. 8,

FIG. 10 is a side elevation in the direction of arrow 10, FIG. 9, partsbeing broken away and parts in section,

FIG. 11 is a plan view looking in the direction of arrow 11, FIG. 9,

FIG. 12 is a diagrammatic view showing part of the structure shown inFIG. 10 in a somewhat different position for producing for instance thetype of fabric shown more specifically in FIG. 2.

FIG. 13 is a diagrammatic view showing structure and method forproducing the fabric shown in FIG. 4,

FIG. 14 is a plan view in the direction of arrow 14, FIG. 8, parts beingomitted, showing the web split into a number of separate tapes orribbons for forming the single structure shown in FIG. 5,

FIG. 15 is an enlarged section on line 15-15, FIG. 2,

FIG. 16 is a diagrammatic View looking in the direc tion of arrow 16,FIG. 15, illustrating the manner in which a single fiber can be joinedto two adjacent yarn-like structures,

FIG. 17 is an enlarged diagrammatic section on line 17-17, FIG. 3,showing the manner in which two webs can be joined as contemplated inthe third form,

FIG. 18 is a diagrammatic plan view showing a variation in the structureshown in FIG. 11 whereby the needles turn in the same direction,

FIG. 19 is a view similar to FIG. 15 but modified to aoeaese o: show thefiber relation produced by the variation shown in FIG. 18,

FIG. 20 is similar to FIG. 17 except that the coiling has been done bythe structure shown in FIG. 18,

FIG. 21 is a side view on an enlarged scale of a needle such as can beused with the invention,

FIG. 22 shows a fabric such for instance as set forth in FIG. 2 innormal size in full lines and in stretched size in dotted lines,

FIGS. 23 to 26 show fabrics of different forms but all of the generaltype shown in FIG. 4,

FIG. 27 is a diagrammatic plan view of a fabric made according to theinvention showing various fiber relations,

FIGS. 28 to 31 show modified forms of needles which can be used,

FIG. 32 is a structural view showing mechanism for driving the needles93 shown in FIG. 13.

Referring more particularly to FIG. 6 which diagrammatically shows amachine to produce the type of fabric illustrated in FIG. 1, frame 11has upright posts 11 which support a table 12 having a bearing 13slidable on each post 11. Extending over and secured in fixed positionon the table is a web supporting plate 14 provided with perforations 15to register with other perforations 16 in a second plate 17 mounted overthe plate 14. The plate 17 is mounted for rising and falling motion andhas end supports 18 which normally rest on fixed stops 19 which limitdown motion of plate 17.

The machine has a shaft 21% driven in any convenient manner to which issecured a crank 21 connected by links 22 to feed arms 23 rockable aboutfixed studs 24. Each arm 23 has a feed pawl 25 which meshes with aratchet wheel 26 rotatable on the corresponding stud 24 and secured to apulley 27. Each pulley drives a belt 28, the belt at the left driving afeed pulley 29 for a flexible Web feeding belt 30 trained around anidler pulley 31. The belt 23 at the right drives a pulley 32 for aflexible takeoff belt 33 trained around an idler pulley 34. A take-offboard 35 receives material fed to it by belt 33. Hold pawls 36 preventretrograde motion of ratchet wheels 26.

A cam 40 is secured to shaft 20 and has a low dwell 41, an incline 42, ahigh point 43 and a decline 44. The cam engages a roll 45 rotatablymounted on the underside of table 12. Rotatable needles N to bedescribed in detail hereinafter are normally located above plate 17 inregister with the openings 16 in the top plate and 15 in the bottomplate.

In the operation of the machine shown in FIG. 6 the web W1, which ismade of a large number of loosely assembled fibers, is fed by belt 30 tothe space between plates 14 and 17 when the low area 41 of cam 40 haslet the roll 45 and table 12 down to their low positions. At this timethe crank arm 21 will be giving feeding strokes to pawls 25 to advancebelts 3th and 33 to feed the webbetween the plates 14 and 17. When thecrank arm has made a half turn and starts a reverse motion of the feedpawls 25 the cam 40 will lift the table 12 and plate 14 to elevate theweb against the plate 17 and lift it off the supporting stops 19,thereby subjecting the web to some restraint. As the cam continues toturn the plates 14 and 17 and also the web rise so that the needles Ncan pass through the holes 16 and rotate in the web to gather fibersinto coiled form at spaced intervals as shown for instance at S1,FIG. 1. The holes 15 are provided in plate 14 to permit the needles togo entirely through theweb ifthis is desired. As the crank 21 continuesthe idle motion of the pawls the cam 41 continues to turn and lower theplate 14. The plate 17, by its Weight, will move the web down away fromthe needles and come to rest on the stops 19. This will complete theoperation with respect to a section of the web and the belt 33 will thenmove the treated web onto the take-off table or board 35 as the belt 341feeds the next section of web between plates 14 and 17. In this way theweb is provided with transverse reenforcing areas of coiled fibers someat least of which extend into adjacent parts of the nontreated web tohave frictional holding contact therewith.

The needles may be mounted and operated as shown for instance in FIGS. 7and 9. In FIG. 7 the driving motor M has a drive pulley 46 connected bybelt 47 to driven pulley 4t) secured to the upper end of a verticalshaft 49. As shown more particularly in FIG. 9 the shaft 49 extends downthrough a top plate 59 and has secured thereto a gear 51 and continuesbeyond the latter and has mounted on the lower end thereof a chuck 52 inwhich the upper end or shank of a needle N is secured. Other chucks 53similar to chuck 52 are mounted on vertical shafts 5 1 each having agear 55 secured thereto. The gears 51 and :55 mesh, adjacent gears andneedles turning in opposite directions. The vertical position of thechucks is determined by a second plate 56 vertically adjustable by nuts57 on upright screws 58 the lower ends of which are secured to the frame52.

As the motor M turns it causes rotation of shaft 49 which in turn causesrotation of all of the needles and this arrangement can, if desired, beutilized to drive the needles N which are shown in FIG. 6. The lower endof each needle is provided with a barb B offset slightly from the shankof the needle and it is the barb on each needle which gathers certain ofthe fibers into the yarnlike structures S1 of FIG. 1. The shafts 49 and54 have collets 60 which engage the under side of plate 56 to limitupward motion of the chucks and needles. The gears which are secured tothe shafts rest on collars or washers 61 supported by the top of plate56. In this way vertical adjustment of the plate 56 determines thepositions of the lower ends of the needles.

When making the fabric shown in FIG. 2 from a single web of fibers theweb W2 is fed into a drum 65 which can be turned by means of gearreducer 66 shown in FIG. 7 as being driven by a connecting shaft 67turned by the motor M. The needles shown in FIG. 12 have been disposedto operate at an angle but in other respects the driving mechanism willbe as already described in connection with FIG. 9. The web W2 is fed inthe direction of arrow 11, FIG. 12, and the free ends of the :needlesterminate close to the friction, soft rubber, surface 68 of the drum orcylinder 65. The ends of the needles have the barbs on them extendedinto the web and rotate at a speed sufficient to gather fibers intoyarnlike assemblages or coils S2 which run lengthwise of the web, theseyarn-like structures being to the left of the needle as viewed in FIG.12.

When producing the fabric shown in FIG. 3 the needles can have thedisposition shown in FIG. 9, that is, upright with their barbed lowerends terminating near the nip between two cylinders 70 and 71 which turnin opposite directions as indicated by arrows b and c, FIG. 10. Theseare the drums which are shown in FIGS. 7 and 8 and are driven by thegear reducer 66 so that their angular speed is considerably less thanthe rotational speed of the needles. Two webs W3A and W33 are trainedrespectively over the upper parts of the cylinders 7t) and 71 which maybe similar to the drum or cylinder 65. As the drums 7t and 71 turn theydraw the webs down to the space or nip between them and cause the twowebs to come into surface engagement with each other at a pointapproximately at the lower end of the needles. As the needles turn theirbarbs collect fibers from each of the two webs W3A and W3B intoyarn-like structure S3 and in this way unite the two webs into a singleweb W3 which corresponds to the web shown in FIG. 3. The lower part ofFIG. 3 shows the web W3A as at the top and the web W3B as at the bottomwith the yarn-like structures S3 connecting these two webs to form thesingle united web W3. As shown in FIG. 8 the fabric we is led downaround guide rolls and then to a windup roll 74 which can be driven fromthe reducer 66 somewhat after the manner of driving cloth rolls inlooms. A

similar wind-up drum or roll can be provided to collect each of thevarious products set forth herein.

Experience shows that the barbs B can occupy several different positionswith respect to the line showing the centers of the two cylinders 70 and71, that is, they can be slightly above the line, on it, or slightlybelow it. Whatever their position it is desirable that the two webs beunder some compression and that the barbs turn on axes which lie on theplane of contact of adjacent surfaces of the two webs W3A and W3B. Thesingle web shown in FIG. 2 can be passed between the two rolls 7t) and71 if desired, and it need not necessarily be made as indicated in FIG.12.

As shown more particularly in FIG. 9 web guide means 80 are provided tocompress the webs somewhat before they reach the positions of mutualengagement. This means also prevents the webs from ascending the shanksof the needles and further provide means to arrest vibration of theneedles. The means 80 comprises two arcuate wings 81 and 82 extendinglengthwise of the rolls 70 and 71 and having their upper ends secured asat 83 to plate 56. These wings are joined at their lower ends 84 throughwhich extend vertical holes 85 which receive the shanks of the needles.

FIGS. 13 and 32 illustrate the structure by which the fabric shown inFIG. 4 is produced. A roll 90 feeds a web W4 to the first set of needles91 which produces yarn-like structures S41 on one side of the web W4.The latter then moves to a second roll 92 and a second set of needles 93produces yarn-like structures S42 on the opposite side of the web. Thelatter is then led over a roll 94 to a wind-up mechanism (not shown)similar to that shown in FIG. 8. Equal gears 86 cause the rolls torotate as indicated and may be driven from mechanism 66 as shown in FIG.7. The shaft 49 can be driven as indicated in FIG. 7 and drive theneedles 91 very much as indicated in FIG. 9. A vertical shaft 87 isconnected by equal bevel gears 88 to a driven shaft 89 similar to shaft49 and operatively connected as indicated in FIG. 32 to the needles 93.

FIG. 18 shows how the needles of a bank can all be rotated in the samedirection. Plate 95 similar to plate 56 replaces the latter and hasrotatable thereon pinions 96 which mesh with gears 97 smaller indiameter than gears 51 and 55. A central vertical shaft 98 is similar toshaft 49 and other shafts 99 are similar to shafts 54. In this way allthe needles turn in the same direction as distinguished from the formshown in FIG. 11 wherein adjacent needles turn in opposite directions.The reason for providing these two types of drive for the needles willbe set forth hereinafter.

The single yarn-like structures such as shown in FIG. 5 can be producedas set forth in FIG. 14 wherein the web, before reaching the feed roll1%, has been split into thin tapes or ribbons 1G1. A needle 1132 isprovided for each tape and may be mounted and operated as alreadydescribed. As roll and the needles 102 turn the fibers of the tapes willbe gathered into coiled forms S5, but unlike the previously describedforms, the yarnlike structures in this instance are separate and do notform parts of a fabric.

The needles for producing the various forms or structures S1S5 may allhave the same general characteristics shown in FIG. 21. The needle shownin that figure has a straight shank 105 one end of which is adapted tofit into holding means such as the clutches 53 shown in FIG. 9. Theother end or" the shank is formed with the previously described barb Bwhich as shown in FIG. 21 extends obliquely away from the shank and ispointed at 1%. The barb lies preferably all on one side of the axis ofthe shank, projecting beyond the extended cylindrical surface orenvelope of the needle shank. The base 107 of the barb is rounded at 168to merge along a smooth curve with the part of the shank opposite to thepoint 106, and a second smooth curve 16? connects the base with the sideof the shank adjacent to the point.

In the operation of the various forms of the invention the barbs on theneedles engage fibers in various ways and have more effect on somefibers than on others. If the fibers are of a preferred randomdistribution in the web some of them will approach a needle parallel tothe direction of feed of the web and be little affected by the needle.Other fibers may be disposed crosswise of the web feed and Will beengaged either near an end or at a point more or less midway of theends. Still other fibers will be oblique to the direction of travel andmay have one end engaged by one needle and later have the other endengaged by an adjacent needle. Other fibers may not be directly engagedby any needle but will be frictionally touching a fiber that is acted onby a needle and to some extent have its position changed by the firstfiber. Other fibers may be transversely disposed but not be affected bya needle. No attempt is made herein to show all possible arrangementsand dispositions which the fibers can occupy as they move toward theneedles as the web is drawn forwardly. A few specific fiber relationswill be described but they are not by any means to be considered asanything more than representative examples.

The fibers are acted on by two forces one of which moves the web in anonward or forward direction and the other of which arises from therotating needles and produces the coiling of the fibers. The onward feedtends to draw the coils into lengthwise helical form and the needlestend to arrange parts at least of the fibers into spiral form. Many ofthe fibers are therefore both helically and spirally coiled and can bestretched lengthwise due to the helical coiling and can be partlyuncoiled when the fabric is stretched crosswise due to the spiralcoiling. Some uncoiling can occur in the helically wound parts of thefibers incident to crosswise stretch.

In FIG. 15 a single fiber 110 is shown as connected to two adjacentstructures S2 between which a straight part 111 of the fiber extends.The left-hand end of fiber 111) can be considered as having been actedon by a counterclockwise turning needle and the right-hand end by aclockwise turning needle, see FIG. 9. FIG. 16 shows one possiblearrangement of the helically coiled parts 112 and 113 of the fiber 111FIG. 17 shows a fiber 115 disposed similarly to fiber 11% except thatits structures S3 are common to the two webs which they join. FIG. 15shows two fibers 118 and 119 caught into the right and left-handstructures S2 respectively and extending into adjacent parts of thefabric, or to adjacent similar structures (not shown}. Similarly, fibers12th and 121 extend to the right and left from structures S3 in FIG. 17.

FIG. 19 is a view similar to FIG. 15 except that the yarn-likestructures are produced by needles all of which turn in the samedirection, see FIG. 18, and FIG. 20 is similar to FIG. 17 but with thesame exception. The fiber 125 in FIG. 19 passes from the top of one ofthe coiled structures down through the web to the bottom of the adjacentstructure, this being true also in FIG. 20. In FIG. 19 fibers 126 aresimilar to fibers 118 and 119, FIG. 15, and in FIG. 20 two fibers 127and 128, one from the upper web and the other from the lower, are shownconnected to the left-hand yarn structure 53.

FIG. 22 illustrates diagrammatically a valuable property possessed bythe fabrics already described. Taking the second fabric as an example,and referring to FIGS. 15 and 16, the fabric W2 may have an originallength e but because of the helical coiling shown in FIG. 16 the lengthcan be stretched or increased to f. The original width g can beincreased to the width k due to uncoiling of the spirals shown in FIG.15, or to uncoiling of the helices. On release of the stretching forcesthe helical and spiral coils will tend to return to their originalforms. The fabric is thus seen to possess considerable elasticity 7 dueto the ceiling of the fibers. This property is possessed by other of thefabrics, such as W3 and W4.

In the fabric W1 the yarn-like structures S1 are short and transverse ofthe plane of the web, but these structures S1 are spirally and helicallycoiled and can unwind in response to lengthwise and transversestretching forces.

When a single web is being processed, as in FIG. 12, or when being fedby one of the drums in FIG. 10-, the yarn-like structure 52 is likely tobe nearer one side of the web than the other and it is for this reasonthat the method set forth in FIG. 13 can produce the fabric W4. FIGS.23-26 show diagrammatically some of the forms of fabric W4 withparticular reference to the direction of rotation of the needles shownin FIG. 13.

In FIG. 23 the direction of coiling for the top structures S41 isclockwise whereas for the lower structures S42 the direction iscounterclockwise. The structures S41 and S42 are staggered as shown sothat if the fabric is subjected to a later compressing operation thestructures of the two series can nest close to or between each other.

In FIG. 24 the top series S41 is made by needles operated as in FIG. 9whereas the bottom series is made by needles turning as for the bottomseries in FIG. 23.

In FIG. 25 both top and bottom series are coiled clockwise, while inFIG. 26 both series are formed by needles which rotate in oppositedirections for each series.

As already mentioned the fibers can assume a great many differentpositions and relations only a few of which will be described inconnection with FIG. 27. In that figure a fiber 130 is shown coiled intothe left-hand structure S2 and having a free end 131 which hasfrictional holding relation with the free end 132 of another fiber 133coiled into the central structure S2. Another fiber 134 coiled into thelefthand structure has a free end 135 which has frictional holdingrelation with an uncoiled fiber 136 lying between two adjacentstructures but not directly connected to either of them. Other fibers137 are not connected directly to any structure S2, and fiber 138similar to fiber 110 is shown as frictionally engaged with another fiber139 not connected to any structure S2. Other of the fabrics can havesimilar fiber relations.

In FIG. 23 the series of structures S41 and S42 are shown as crossconnected by fibers 144 which, like others similar to them but notshown, tend to bind the two series together, the ends of fiber 149 beingcoiled into structures on opposite sides of the web. Similarly, fibers141, 142 and 143 in FIGS. 24, 25 and 26 respectively bind the structuresS41 and S42 in each form to each other.

The invention has been practiced with a web containing 25% viscosefibers and 75% acetate fibers. Tests were made of samples of the web oneinch wide, six inches long, and about one-quarter inch thick. The testsshowed an average breaking strength of the unprocessed web samples of4.3 grams, whereas the processed samples containing 21 single lengthwiseyarn-like structure, as S2, had a breaking strength averaging 23.4grams. The coiling of the fibers therefore resulted in an increase ofmore than 500% in the strength of the web. Both the processed andunprocessed samples had in them approximately the same number of fibers.

The invention is not limited to the specific types of fibers mentionedand the fibers can be of different lengths and may be either oriented,as lengthwise of the web, or placed at random.

The separate tape or ribbon webs shown in FIG. 14 can be cut orotherwise derived from a wider web in any approved manner. One methodcould, for instance, be similar to the procedure set forth in AmericanWool Handbook, 1948, published by Textile Book Publishers, Inc., NewYork city, the chapter on Blending and Woolen Carding, section on TapeCondensers.

A needle which has operated successfully had a shank diameter of 0.039inch and the point of the barb traveled in a circular path having adiameter of 0.044 inch. The

length of the barb was 0.1l3 inch from its point to the point of mergingof curve with the shank. The needle was operated at 400 rpm. and thefeed of the web was about two feet per minute. Other speeds of needlerotation and web feed were found to be satisfactory and ty es of barbshaving dimensions approximating those given but of the same generalshape were found to be satisfactory. The smaller the offset of the pointfrom the shank axis the smaller will be the diameter of the yarn-likestructure. The curves 1% and 1&9 were honed in order to insure clearanceof the structures S1 S5 from the needles as the webs advanced.

While reference has been made to the spiral arrangement of parts atleast of the coiled fibers, it is to be understood that the feature setforth in FIG. 22 for instance, especially the transverse stretching, canbe derived from the helically wound parts of the fibers as well as anyparts which may be spirally wound. Since the coil arrangement is madearound a needle having an appreciable diameter the coils at one point intheir formation may be hollow, but it is found that as the operationproceeds the yarn-like structures tighten on themselves so that in thefinished product there is only a small axial hollow observable in thestructures. Further, the barbs of the needles pick up the fibers fromthe web at an operating zone at the ends of the needles as suggestedeither in FIGS. 8, 10 or 12.

In all forms of the invention the method effects a gathering of fibersor parts thereof drawn from a web and subjecting the gathered fibers orparts thereof to rotary action which orient them partly spirally andpartly helically, and in all forms the yarn-like structures are movedaway from the needles by wind-up rolls such as that shown at 74 in FIG.8 so that the structures can clear the needles as other fibers approachthe barbs. The needles are partly at least embedded in the web and thediameter of the path of rotation of the point of the barb is less thanthe thickness of the web. In the form shown in FIG. 1 the coilstructures are shown substantially at right angles to the plane of theweb but they could, if desired, be disposed at an angle by anappropriate modification of the machine shown in FIG. 6. In other formsthe web at the zone of operation is moving more or less parallel to theaxis of the needles and for this reason the web can be movedcontinuously instead of intermittently as contemplated in FIG. 6. Thesingle web shown in FIG. 2 can be made either as suggested in FIG. 12 orby the structure shown in FIG. 10 wherein only one web will be fed overone of the drums.

The needles are preferably so mounted that their barbs do not abrade theconvex rubber surfaces of the drums and when two drums are used as inFIG. 10 even a single web can be subjected to some compresssion as itapproaches the operating zone. It is observed in operation that thefibers may gather around the part of the needle shank near the barb butthey are found to slip off the shank and the barb as the web is fedforwardly. Means are provided for changing the relative speed of theneedles with respect to the turning of the drums as for instance byreplacing the pulleys 46 and 43 by other pulleys of different diameterwhich will alter the speed of the needles with respect to the rate atwhich the drums are turned. Another means for changing the relativespeed of the needles and drums is to employ a type of reducer 66 whichhas a variable drive built into it.

In the foregoing the needle described is of the form shown in FIG. 21,but there are other forms of needles which can be used as shown in FIGS.28-31. In FIG. 28 the lower end of the cylindrical shank 150 is bentlaterally as at 151 and terminates in a cone 152. In FIG. 29 the lowerend of the shank 155 is formed with a straight oblique surface 156 whichleads to a barb or spur 157 which projects beyond the envelope of theshank 155. In FIG. 30 the shank 16d is formed with several downwardlypointed projections or spurs 161 and the lower end of '9 the shank comesto a point 162. In FIG. 31 the shank 165 has its lower end 166 broadenedby flattening and two prongs, projections, or spurs 167 and 168 areformed partly by the broadened end 166 and partly by the concave bottom169 of the end 166.

The pointed parts of the various forms of needles may be considered asbarbs, burrs, spurs, prongs or projections, but in the broader sense theneedles of whatever form act due to their rotation to gather fibers intothe yarn-like structures already described. The needles may in fact beformed otherwise than as shown and may be formed with a straight shankwetted with a liquid, preferably slightly adhesive, to collect thefibers as the needles turn. The needle shanks may be fluted to retainthe liquid and the latter be applied to the needles in small jets.

Although the form of product shown in FIG. has been described as madefrom tapes or ribbons of fibers formed as such before reaching theneedles, it may also be made by moving a wide web to the needles andcutting it into tapes at the needles. In fact, cutting may be omittedand reliance placed on the needles to separate the structures $5 fromthe web.

The guard 80 shown in FIG. serves not only to effect some compression oftheweb near the operating zone of the needle barbs, but also tends toarrest vibration of the barbed ends of the needles and furthermore isfound to prevent fibers from climbing up the shanks of the needles. Theplate 17, FIG. 6, also serves to prevent fibers from climbing up theneedles.

In any of the coils shown in any of the forms described the fibers maybe set in the coiled configuration by means well known in textile artssuch as the heat-setting of thermoplastic fibers or chemical treatmentswhich produce memory effects, thus enhancing the elastic behavior of theweb system as set forth in FIG. 15.

Having now particularly described and ascertained the nature of theinvention and in What manner the same is to be performed, what isclaimed is:

1. In mechanism for operating on a web of loosely assembled fibers, arotatably mounted needle having an end thereof projecting into the weband provided with a barb, means to rotate the needle around itslengthwise axis to cause the needle and barb to gather fibers from theweb into a coiled assembled group around the needle, and means to causerelative motion of the web and needle in a direction to separate thegroup from the needle as the needle rotates.

2. The mechanism set forth in claim 1 wherein the needle has a shankrotated by said first named means about the axis of the needle and thebarb projects at one side of the shank beyond the envelope of the shank,and a rounded part of the barb merges along a smooth curve with theopposite side of the shank.

3. The mechanism set forth in claim 2 wherein the part of the barb atsaid one side of the shank merges with said one side along a smoothcurve.

4. The mechanism set forth in claim 2 wherein all of the barb is locatedat one side of the axis of the needle.

5. The mechanism set forth in claim 2 wherein the barb extends obliquelyaway from said axis of the needle and the point of the barb is the partof the latter farthest from said shank.

6. In mechanism for operating on a web of loosely assembled fibers,means supporting the web, a rotary needle having a barb on the endthereof, means to cause relative motion between the web and needlelongitudinally of the latter, and means to rotate the needle around itslengthwise axis during said relative motion to cause the barb to drawfibers from the web and assemble them in coiled yarn-like arrangement,said relative motion causing the fibers thus assembled to moverelatively to the needle in a direction away from the latter.

7. The mechanism set forth in claim 6 wherein the supporting means movesthe web during said relative motion toward and from the needle.

8. In mechanism for uniting two webs of loosely assembled fibers, a pairof drums having parallel axes and having their peripheries spaced aslight distance apart, means to rotate the drums in opposite directionsto draw webs, one on each drum, into mutual engagement between thedrums, needles each having a barb on the end there of, means supportingthe needles to position their barbs adjacent to the nip between thedrums and projecting into the webs, and means to rotate the needles tocause the barbs to gather fibers from each web into a yarn-likestructure connecting both webs.

9. In mechanism for uniting two webs of loosely assembled fibers, a pairof drums rotatable about parallel axes with adjacent parts of the drumsspaced slightly and defining a nip, turning means to rotate the drums inopposite directions, a plurality of aligned rotary needles each having abarb on the end thereof, the webs being trained around parts of thedrums, one web for each drum, and advanced into engaging relation witheach other when the drums rotate, means supporting the needles withtheir barbs adjacent to said nip and extending into the webs, anddriving means to rotate the needles as the turning means rotate thedrums to cause the barbs to gather fibers from each web and coiltheminto a yarn-like structure around the needle as the webs are advanced bythe drums, each yarn-like structure containing fibers drawn from bothwebs and joining the webs.

10. In mechanism for operating on a web of loosely assembled fibers, aroll mounted for rotation about an axis, means to rotate the roll aboutsaid axis to feed a web on the roll to an operating zone, a series ofaligned rotatably mounted needles each having a barb on the end thereoflocated at said zone and projecting into the web, means to rotate theneedles as the roll rotates to gather fibers from the web into coiledform, and means to draw the web and fibers in coiled form away from theneedles.

11. In mechanism for operating on a web of loosely assembled fibers, apair of drums having parallel axes and having their peripheries spaced aslight distance apart, means to rotate the drums in opposite directionto feed the web into them, needles each having a barb on the endthereof, means supporting the needles to position their barbs adjacentto the nip between the drums and projectinginto the web, and means torotate the needles to cause their barbs to gather fibers around them.

12. In mechanism for operating on a web of loosely assembled fibers, aplurality of rotatably mounted needles each having a barb on the endthereof, a drum rotatable to feed the web to an operating zone, meanssupporting the needles with their barbs projecting into the web at theoperating zone, and driving means to rotate the needles and drumsimultaneously to cause the barbs to gather fibers from the web intocoiled form as the drum feeds the web to said zone, and means to drawthe web away from said zone.

13. The mechanism set forth in claim l2 wherein provision is made tochange the relative rates of rotation of the needles and drum.

14. In mechanism for acting on an elongated web of loosely assembledfibers, means to move the web in the direction of its length, a rotaryneedle provided with a barb extending into the web, means to rotate theneedle around its lengthwise axis to cause said barb to gather thefibers into a coiled group, and means to draw the group away from saidneedle as the latter rotates.

15. In mechanism for acting on a web of loosely assembled fibers, meanssubjecting the fibers in areas spaced across the web to localized rotarymotion to produce separate discrete groups of coiled fibers, and meansto wind up the groups in an operation which draws them away from thepoints in their length where they are subjected to said rotary motion.

16. The mechanism set forth in claim 15 wherein the 1 1 web comprisesseparate side by side tapes of fibers and a group of coiled fibers isformed from each tape.

17. In mechanism for acting on a web of loosely assembled fibers, meanssubjecting the fibers in spaced areas across the web to localized rotarymotion to gather the fibers of each area into a coiled groupdisconnected from the fibers of the other areas, and means winding upthe groups in an operation which draws them away from the points intheir length where they are subjected to said rotary motion.

18. In a machine for forming nonwoven fabric from a web of looselyassembled fibers, means moving the web in the direction of the lengththereof, means subjecting the fibers on one side of the web to rotaryaction to form groups of yarn-like structures comprising coiled fibersdrawn from said side as the web moves, and other means subjecting fiberson the opposite side of the web to rotary action to form fibers drawnfrom said opposite side into coiled yarn-like structures, said means andother means causing fibers of the fabric to be coiled into twoyarn-likestructures on opposite sides of the web.

19. The structure set forth in claim 18 wherein said other means formsyarn-like structures on said opposite side which are staggeredtransversely of the web with respect to the yarn-like structures formedby the first means.

20. In a machine having a roll to feed a web of loosely arranged fibersto an operating zone to form a nonwoven fabric, a needle having a shankand barb thereon at said zone, means to rotate the needle to cause thebarb to gather fibers from the web into a yarn-like structure, and aguard over the web conforming generally to the curvature of the roll andcompressing the web as the latter approaches said zone.

21. In a machine having a roll to feed a web of loosely arranged fibersto an operating zone to form a nonwoven fabric, a needle having a shankand barb thereon at said zone, means to rotate the needle to cause thebarb to gather fibers from the web into a yarn-like structure, and

12 a guard over the web conforming generally to the curvature of theroll and terminating at a point spaced from said zone and acting toprevent fibers from accumulating around the needle along the shankthereof at points spaced from the barb.

22. The machine set forth in claim 21 wherein said guard acts to preventvibration of the needle.

23. The machine set forth in claim 21 wherein the needle shank passesthrough a hole in the guard and the latter prevents vibration of theneedle and also prevents fibers from moving along the needle shank in adirection away from the barb.

24. 'In mechanism for acting on a web of loosely as sembled fibers,rotary means engaging some at least of the fibers of the web effectivewhen rotated to gather the fibers around it to form a coiled yarn-likestructure, means to rotate the rotary means, and means to draw saidstructure awayfrom the rotary means as the rotary means rotates.

References Cited in the file of this patent UNITED STATES PATENTS1,400,302 Maussner Dec. 13, 1921 1,454,049 Genung May 8, 1923 1,898,027Winslow Feb. 21, 1933 1,962,950 Cochrane June 12, 1934 2,148,511 Spechtet al Feb. 28, 1939 2,297,440 Szucs Sept. 29, 1942 2,372,484 Gould Mar.27, 1945 2,377,564 Lundgren June 5, 1945 2,528,793 Secrist Nov. 7, 19502,672,673 Shaw Mar. 23, 1954 2,853,847 Keeler et al Sept. 30, 19582,893,105 Lanterbach July 7, 1959 2,920,373

Gresham Jan. 12, 1960 OTHER REFERENCES Fiberglass Products for PaperMaking, Owens-Corning Fiberglas Co., February 1954 (page 4 pertinent).

